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The commissioning of the MAX IV synchrotron radiation facility in Lund marks the dawn of a new generation of storage-ring-based light sources. This new generation delivers one order of magnitude higher performance and allows realization of groundbreaking experiments on a variety of systems and materials at the atomic and molecular levels. This paper reviews the conceptual basis of the MAX IV design, briefly summarizes the most recent accelerator commissioning results and focusses on exploring a future development path for the MAX IV 3 GeV storage ring aimed at achieving the diffraction limit at hard x-ray wavelengths. [ABSTRACT FROM AUTHOR]

Abstract: Metagenomic libraries represent subsamples of the total DNA found at a study site and offer unprecedented opportunities to study ecological and functional aspects of microbial communities. To examine the depth of a community sequencing effort, rarefaction analysis of the ribosomal small subunit (SSU/16S/18S) gene in the metagenome is usually performed. The fragmentary, non-overlapping nature of SSU sequences in metagenomic libraries poses a problem for this analysis, however. We introduce a software package – Megraft – that grafts SSU fragments onto full-length SSU sequences, accounting for observed and unobserved variability, for accurate assessment of species richness and sequencing depth in metagenomics endeavors. [Copyright &y& Elsevier]

Abstract: Ventriculomegaly at term age is an important predictor of neurologic outcome in preterm infants. Previous studies have found only poor correlations between two-dimensional (2D) cranial ultrasound (US) measurements of lateral ventricles and volume measurements using three-dimensional (3D) magnetic resonance imaging (MRI). Paired cranial MRI and US scans in a population based cohort of 28 extremely preterm infants were obtained at term equivalent age. A 3D MRI volume and five different 2D ultrasound measurements were assessed for each lateral ventricle. Correlations and interobserver variability were calculated. Reliability of US measurements and correlations between MRI volumes and US measurements of the frontal horns and ventricular midbody were consistently good. The highest correlation was achieved by combining the coronal frontal horn measurements to a frontal horn product (r 2 = right 0.94, left 0.95). Our study underlines the value of cranial ultrasound measurements in neonatal care and follow-up. (E-mail: s.horsch@gmx.de) [Copyright &y& Elsevier]

In this paper we present a case-study in which the tool Uppaal is extended and applied to verify an audio-control protocol developed by Philips. The size of the protocol studied in this paper is significantly larger than case studies, including various abstract versions of the same protocol without bus-collision handling, reported previously in the community of real-time verification. We have checked that the protocol will function correctly if the timing error of its components is bound to ±5%, and incorrectly if the error is ±6%. In addition, using Uppaal’s ability of generating diagnostic traces, we have studied an erroneous version of the protocol actually implemented by Philips, and constructed a possible execution sequence explaining the error. During the case-study, Uppaal was extended with the notion of committed locations. It allows for accurate modelling of atomic behaviours, and more importantly, it is utilised to guide the state-space exploration of the model checker to avoid exploring unnecessary interleavings of independent transitions. Our experimental results demonstrate considerable time and space-savings of the modified model checking algorithm. In fact, due to the huge time and memory-requirement, it was impossible to check a simple reachability property of the protocol before the introduction of committed locations, and now it takes only seconds. [ABSTRACT FROM AUTHOR]